Quality evaluation of the surface waters entering the Doñana National Park (SW Spain)

Surficial waters entering the Doñana National Park were sampled and analysed for 20 parameters over 12 years at more than 30 sampling sites. Different types of pollution characterize the different water networks entering Doñana. The waters entering from the north are little polluted or only polluted by outlets from small villages and/or effluents from industries of transformation of agricultural products. Acid mine-waters with high heavy metal concentrations skirt and enter Doñana from the east. Finally waters of marine origin enter Doñana from the south. The eastern and northern water networks are very dynamic, and flood Doñana frequently. The importance and variation of the pollution carried through the various water networks under different flow conditions are discussed.